Noam Shazeer Leaves Google for OpenAI After $2.7 Billion Return

Noam Shazeer is leaving Google for OpenAI. He announced the move on June 18, less than two years after Google paid $2.7 billion to get him back from Character.AI. Shazeer co-led Gemini at Google as VP of Engineering and co-authored "Attention Is All You Need" - the 2017 paper that gave the world transformers and, by extension, every large language model that followed. His role at OpenAI has not been disclosed.

Google has not commented publicly on the departure.

Google's $2.7 Billion Hiring Deal Lasted 22 Months

Shazeer left Google first in 2021. He co-founded Character.AI, a companion chatbot company that grew rapidly before Google struck a licensing deal with the startup in August 2024, paying $2.7 billion for non-exclusive access to Character.AI's technology. Shazeer and several colleagues returned to Mountain View as part of that arrangement. For Google, losing the transformer paper's co-author to a direct competitor barely 22 months after paying $2.7 billion to hire him back is a difficult result to explain to anyone.

Shazeer Co-Wrote the Paper Every Major AI Model Runs On

Shazeer and seven colleagues at Google Brain published "Attention Is All You Need" in 2017, introducing the transformer architecture that became the foundation of modern AI. Every major model in production today - GPT-5.5, Gemini, Claude Opus 4.8, Llama, and hundreds of open-source alternatives - builds directly on that paper's core design. All of them. Shazeer joining OpenAI puts him at the lab iterating on that architecture with the largest training budget in the industry.

For developers, a researcher of Shazeer's depth landing at OpenAI suggests the next generation of models may shift at the architectural level, not just at parameter scale. His role is unconfirmed. OpenAI has said nothing beyond acknowledging his arrival.

Google Loses Its Gemini Co-Lead at a Competitive Moment

Shazeer's departure comes two weeks after Apple chose Google Gemini to power the rebuilt Siri AI in iOS 27 - arguably Gemini's biggest commercial win to date. Google still employs hundreds of researchers on Gemini, and the model itself continues to ship. But losing Shazeer leaves a gap at the top of the Gemini team at a moment when the AI race between OpenAI, Anthropic, and Google is as close as it has ever been.

OpenAI currently expects GPT-5.6 to launch before July, with Polymarket traders placing 83% probability on a release window of June 22 through June 28. Whether Shazeer contributed to that model or will work on later generations is unknown.